The Tokyo District Court found three former company executives guilty Friday of professional negligence resulting in the death of a 6-year old boy who was crushed in an automatic door at the Roppongi Hills complex in March 2004.

Hisanobu Kubo, former director of door manufacturer Sanwa Tajima Corp., was sentenced to a suspended 14-month prison term, while Yuzo Tada, former managing director of complex operator Mori Building Co., and Yukihiro Koyama, former head of the Roppongi Hills management operations room, were sentenced to suspended 10-month terms.

All three sentences were suspended for three years.

Presiding Judge Hironobu Murakami noted there had been many similar accidents involving automatic revolving doors at Roppongi Hills prior to Ryo Mizokawa's death.

These included an incident four months earlier, when a 6-year-old girl was seriously injured.

The three former executives could therefore have predicted the accident, Murakami ruled.

The three men instead neglected to adopt adequate safety measures and continued to operate the revolving door for the public without due care, the judge said.

"It was the three defendants' concurring negligence that . . . caused the death of Mizokawa," Murakami said.

All three had pleaded guilty to the charges.

Mizokawa, from Suita, Osaka Prefecture, got his head stuck between the revolving door and the door frame as he rushed ahead of his mother into an entrance of the Mori Tower building. He sustained brain damage and died.

After the verdict, Koichi Mizokawa, the boy's father, issued a statement in which he blasted the suspended sentences.

"I am bitterly disappointed and sad that (the defendants) received suspended sentences even though my son's precious life was taken," he said. "I cannot bear the fact that this means the defendants can go on with their daily lives without any effect."